Door latch



Sept. 20, 1.955 G. w. sLoPA ETAL DOOR LATCH Filed April 22, 1952 47 44ev 463; f2

United States Patent O DOOR LATCH George W. Slopa and Robert E. Slopa, Chicago, lll.

Application April 22, 1952, Serial No. 283,678

2 Claims. (Cl. 292-165) The invention relates to improvements in door latches, and is more particularly concerned with a heavy duty latch of the type used to secure a door of a refrigerator closed, and which embodies novel structural features operable to permit release of the latch from the inside of the refrigerator even when the latch is locked against release from the outside.

The latch disclosed in this application is concerned generally with that type of latch which is required to maintain a closure, such as the door of a walk-in refrigerator in closed position. Latches of this type now in general use have auxiliary release means on the inside face of the door and are provided with means to receive a lock, so as to prevent unauthorized manipulation of the conventional latch actuating handle located on the outside of the door. When such latches are locked it is impossible to release the latch from the inside of the refrigerator by operation of the auxiliary release means. Obviously, this is a serious disadvantage because, on occasion, a person is trapped within the refrigerator and the handle is locked. Under such circumstances, serious illness and possible death may result.

The latch of the present invention is structurally designed to afford adequate means for latching the door, means to receive a lock so as to prevent operation of the conventional latch actuating handle and novel means to render said lock means inelfective when the auxiliary release means on the inside face of the door is operated. lt is, therefore, an object of the present invention to provide a door latch embodying the foregoing characteristics.

Another object of the invention is to provide a door latch having novel means to permit the unlatching of the door from the side of the door opposite to that upon which the latch is mounted.

Another object is to provide a door latch with novel releaseable means to coact with a locking element.

Another object of the invention is to provide a ruggedly constructed, heavy duty, door latch of the character described, which is not expensive to manufacture, is positive in operation, easy to install and highy eflcient in use.

Another object is to provide a novelly constructed door latch mechanism with a novel association of parts arranged to coact to prevent unauthorized latch actuation from onek side of the door without preventing its actuation from the other side of said door.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel features of construction, arrangement and combination of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the form, proportion, size and minor details of the structure may be made without departing from the spirit or sacrificing any of the advantages of the invention.

l' assembly or repair, should the occasion arise.

2,718,421 Patented Sept. 20, 1955 ICC For the purpose of facilitating an understanding of our invention, we have illustrated in the accompanying drawings a preferred embodimentthereof, from an inspection of which, when considered in connection with the following description, our invention, its mode of construction, assembly and operation, and many of its advantages should be readily understood and appreciated.

Referring to the drawings in which the same characters of reference are employed to indicate corresponding or similar parts throughout the several figures of the drawings:

Fig. 1 is a front elevational view of a latch mechanism embodying the features of the present invention, showing the latch mounted.

Fig. 2 is a longitudinal central sectional View of the latch taken substantially on line 2-2 of Fig. 1, showing parts in elevation.

Fig. 3 is a sectional detail view taken substantially along line 3-3 of Fig. 2.

Fig. 4 is a longitudinal central sectional View like Fig. 2, but showing the latch mechanism in unlatched position.

The latch mechanism of the present invention is en closed within a substantially rectangular housing 11, which includes a mounting flange 12 through which lag bolts 13 or other securing means are inserted for securing the housing in place upon the outside face of a door 14. The door 14 may be a closure of any conventional structure adapted to close an opening, herein identified at 15, in a wall 16 of a refrigerator or other enclosure.

The housing 11 has a front wall 17, spaced side walls 18 and end Walls 19 and 21. Upon referring to Fig. 2, it will be observed that the side of the housing 11 bearing against the face of the door 14 is open, thus affording access to the interior of the housing for purposes of A slide bolt, generally indicated at 22, is mounted within the housing 11, and it includes a substantially large body portion 23 and a projecting portion 24 of reduced dimensions. The projecting portion 24 extends through an opening 25 in the end wall 19. The body portion 23 has a lug 26 formed integral therewith, which lug is of lesser width than the width of the body portion 23 for a purpose to be described presently. The lug 26 defines a shoulder 27 provided for cooperative engagement by manually actuable means operable to effect movement slidably of the slide bolt in one direction.

The means provided in the present instance to move the slide bolt 22 in one direction consists of a manually engageable handle 28. The handle 28 is disposed on the outside of the housing wall 17, and it may be of any desirable or practical configuration so as to facilitate easy manual engagement therewith. The handle is pivotally mounted, as by means of a pin 29, between a pair of ears 31 formed integral with and projecting outwardly .from the top wall 17. A lateral projection 32 formed integral with the handle 28, adjacent its pivotally mounted end, extends through a slot 33 in the housing wall 17 and is provided with a straight edge 34 adapted normally to bear against the slide bolt shoulder 27. Bearing engagement between the edge 34 and shoulder 27 is maintained by means of a tension spring 35 interposed between the innermost end of the slide bolt 22 and a lug 36 formed integral with and projecting inwardly from the wall 17, as best indicated in Fig. 2.

Upon referring to Fig. 2, it will be observed that the slide bolt 22 has a boss 37, which is received within one end of the tension spring 35, and that the lug 36 also has integral therewith a boss 38, which is received within the other end of said spring. The bosses 37 and 38 tend to retain the spring in position atall times.

It should be quite apparent, at this time, that the spring 35 normally projects the reduced portion 24 of the slide bolt 22 through the end Wall opening 25 so as to cause said `projecting portion normally to engage beneath a stop dog provided on a conventional stop plate 39. When'the handle 28 is engaged and moved about its pivot v29 outwardly away from the housing wall 17, the straight edge 34 of the lateral projection 32 acts against the slide bolt shoulder 27 to urge it against the action of the `spring 35 for withdrawing the projecting portion 24 from beneath the stop dog on the plate 39 thereby releasing the latch and permitting opening of the door. The instant structure is provided with means whereby the slide bolt 22 may be locked against movement upon attempted manipulation of the handle 28. Accordingly` saidslide bolt is provided with a dog 41, which is pivotally mounted on the slide bolt 22 within the housing 11. The pivotal mounting for said dog is shown at 42. The dog consists substantiallyof a one-piece bifurcated structure having side portions, one disposed on each side of the slide bolt body 23, and a connecting bridge portion 43. The bridge portion 43 is located rearwardly ofthe slide bolt lug 26. The dog 41 projects a considerable distance rearwardly of the portion 43 and said dog terminates closely adjacent to the axis of a pair of aligned holes 44 provided in the housing side walls 18.

The holes 44 are adapted to receive, for ready removal, a loclt pin or bar 45 of any suitable type, which bar lies in the path of the dog 41. A pair of springs 46 are arranged about the pivot pin 42 of the dog, one on each side of the lug 26. Upon referring to Fig. 3, it will be observed. that these springs lie in recesses defined by the reduced width of the lug 26, and that one end of each spring bears against a related shoulder 47 on the slide bolt 22, and that the other ends of said springs bear against the bridge portion 43. These springs normally hold the dog in the position illustrated in Fig. 2, in which position one edge thereof is in abutment with a protuberance 48 formed on the inside face of the wall 17. When a lock pin, such as the pin 45 illustrated in Figs. 2 and 4, is extended through the aligned holes 44 in the housing 11, normal movement of the slide bolt into the housing is prevented. Should the latch be locked in the manner described, it is quite apparent that unless special means are provided in the construction of the latch, it would be impossible to open a latched door from the interior of the .enclosure closed by the door. The instant latch structure does, however, embody novel means whereby, even though the latch may be locked in the manner described hereinabove, said latch may be opened easily and quickly from within the enclosure.

Again referring to the Figs. 2 and 3 disclosures, it should be observed that there is provided, within the housing 11, a pair of rock arms 49 and 51. The rock arm 49 is pivotally mounted at 52 and has a tail portion 53 4and spaced portions 54. The portions 54 are spaced apart a suicient distance to lie one on each side of the slide bolt 22. A pin 55 bridges the free ends of the rock arm portions 54 to provide a journal for a roller 56, which roller is adapted to be operable, in a manner to be vdescribed presently, within an opening 57 in the slide lbolt body portion 23. The rock arm portions 54 extend a short distance beyond the pin 55 and are projected laterally in the direction of the locking dog 41, so as to dispose their free end edges 58 normally in abutment with cam-like surfaces 59 formed on an edge of the related portions of the dog 41. It should be apparent that, when the rock arm 49 is rocked in a counterclockwise direction, as viewed in Figs. 2 and 4, the lateral extremities of the arm portions 54 will bear against and impart counter-clockwise movement to the dog 41 about -its pivot 42. Such movement of the dog will .dispose the end of said dog out of the plane of the lock pin 45, thus freeing the slide bolt 22 for its withdrawal into the body of the housing 11. When the dog 41 is thus released, the roller 56 in rock arm 49 will ride along the inclined edge 61 of the slide bolt opening 57 to draw the slide bolt into the housing.

Rocking movement of the rock arm 49 in the manner described in the preceding paragraph is accomplished by manual rocking of the rock arm 51. The rock arm 51 is journalled midway between its ends at 62, and it has its nose portion 63 overlying the tail portion 53 of the rock arm 49. The other projecting end portion of the rock arm 51 is provided with a contact surface 64, against which one end of a push rod 65 bears at all times. The push rod 65 extends through the door 14, or other closure, so as to be easily manipulatable from the inside of the enclosure. It should be quite obvious that when the door latch is locked, as by insertion of the pin 45 so as to prevent its being actuated upon manipulation of the handle 28 provided on the outside of the door 14, said latch may be released instantly upon applying longitudinal pressure to the push rod .65, so as to rock the rocker arms 51 and 49 in the manner described hereinabove to thereby position the dog V41 out of the Path of the lock pin and effect positive withdrawal of the slide bolt 22.

A hole 66 is provided in each housing side wall 18 adjacent the juncture of the front wall 17 and end wall 21 to receive the lock pin 45 for storage when the latter is removed from the holes 44.

It is believed that our invention, its mode of construction and many of its advantages should be readily understood from the foregoing without further description, and it should also be manifest that while a preferred embodiment of the invention has been shown and described for illustrative purposes, the structural details are nevertheless capable of wide variation within the purview of our invention as defined in the appended claims.

What we claim and desire to secure by Letters Patent ofthe United States is:

1. In a latch of the character described, a housing, a slide bolt .in said housing, means normally operable to move the slide bolt in one direction, a dog movable bodily with the slide bolt, means normally holding the dog in a predetermined position relative to the slide bolt, stop means insertable in the path of the dog to prevent movement of the dog and slide bolt in said one direction, a manually actuableelement, a rocker arm in said housing engaged and rocked by said element when the latter is actuated, and a second rocker arm engaged and rocked by the tirst named rocker arm, said second rocker arm including separate means to coact with the dog to move it into a position of non-engagement with the stop means and to then move the slide bolt in said one direction.

2. In a latch of the character described, a housing, a slide bolt in said housing, means normally operable to move the slide bolt in one direction, a dog carried on and movable bodily with the slide bolt, means normally holding the dog in a predetermined position relative to the slide bolt, stop means insertable in the path of the dog to prevent movement of `the dog and slide bolt in said one direction, a push rod, a rocker arm in said housing engaged and rocked by the push rod when the latter is moved in the direction of the housing, a second rocker arm engaged and rocked by the first named rocker arm, said second rocker arm coacting with the dog to move it relative to the slide bolt, and means on said second rocker arm to then move the slide bolt in said one direction.

References Cited in the le of this patent UNlTED STATES PATENTS 1,578,779 Titus Mar. 30, 1926 2,043,787 Wild June 9, 1936 2,156,513 Roedding May 2, 1939 2,415,587 Groeger Feb. 11, 1947 2,424,782 Voight et al July 29, 1947 2,444,819 Freysinger July 8, 1948 2,475,478 Clair July 5, 1949 2,655,395 Groeger Oct. 13, 1953 

